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authorDenys Vlasenko <vda.linux@googlemail.com>2019-05-31 23:39:22 +0200
committerDenys Vlasenko <vda.linux@googlemail.com>2019-05-31 23:39:22 +0200
commit65c34c52df3ed46f0b811d1858c271a373ab6af5 (patch)
tree8c9a08f6ff1b442dbb642995d1870cb2efd87a0d /networking/udhcp/signalpipe.c
parent91755cb16d496d1094f5d81051a1e1e6f27a21c1 (diff)
downloadbusybox-65c34c52df3ed46f0b811d1858c271a373ab6af5.tar.gz
dhcp: get rid of static data signal_pipe
function old new delta udhcp_sp_setup 65 110 +45 udhcp_sp_fd_set 60 59 -1 udhcpd_main 1442 1437 -5 udhcpc_main 2684 2679 -5 signal_pipe 8 - -8 packed_usage 33292 33284 -8 ------------------------------------------------------------------------------ (add/remove: 0/1 grow/shrink: 1/4 up/down: 45/-27) Total: 18 bytes text data bss dec hex filename 952746 481 7296 960523 ea80b busybox_old 952768 481 7288 960537 ea819 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'networking/udhcp/signalpipe.c')
-rw-r--r--networking/udhcp/signalpipe.c31
1 files changed, 22 insertions, 9 deletions
diff --git a/networking/udhcp/signalpipe.c b/networking/udhcp/signalpipe.c
index 2ff78f0f2..81d1fc01a 100644
--- a/networking/udhcp/signalpipe.c
+++ b/networking/udhcp/signalpipe.c
@@ -20,14 +20,14 @@
*/
#include "common.h"
-/* Global variable: we access it from signal handler */
-static struct fd_pair signal_pipe;
+#define READ_FD 3
+#define WRITE_FD 4
static void signal_handler(int sig)
{
int sv = errno;
unsigned char ch = sig; /* use char, avoid dealing with partial writes */
- if (write(signal_pipe.wr, &ch, 1) != 1)
+ if (write(WRITE_FD, &ch, 1) != 1)
bb_perror_msg("can't send signal");
errno = sv;
}
@@ -36,12 +36,25 @@ static void signal_handler(int sig)
* and installs the signal handler */
void FAST_FUNC udhcp_sp_setup(void)
{
+ struct fd_pair signal_pipe;
+
+ /* All callers also want this, so... */
+ bb_sanitize_stdio();
+
/* was socketpair, but it needs AF_UNIX in kernel */
xpiped_pair(signal_pipe);
- close_on_exec_on(signal_pipe.rd);
- close_on_exec_on(signal_pipe.wr);
- ndelay_on(signal_pipe.rd);
- ndelay_on(signal_pipe.wr);
+
+ /* usually we get fds 3 and 4, but if we get higher ones... */
+ if (signal_pipe.rd != READ_FD)
+ xmove_fd(signal_pipe.rd, READ_FD);
+ if (signal_pipe.wr != WRITE_FD)
+ xmove_fd(signal_pipe.wr, WRITE_FD);
+
+ close_on_exec_on(READ_FD);
+ close_on_exec_on(WRITE_FD);
+ ndelay_on(READ_FD);
+ ndelay_on(WRITE_FD);
+
bb_signals(0
+ (1 << SIGUSR1)
+ (1 << SIGUSR2)
@@ -54,7 +67,7 @@ void FAST_FUNC udhcp_sp_setup(void)
*/
void FAST_FUNC udhcp_sp_fd_set(struct pollfd pfds[2], int extra_fd)
{
- pfds[0].fd = signal_pipe.rd;
+ pfds[0].fd = READ_FD;
pfds[0].events = POLLIN;
pfds[1].fd = -1;
if (extra_fd >= 0) {
@@ -74,7 +87,7 @@ int FAST_FUNC udhcp_sp_read(void)
unsigned char sig;
/* Can't block here, fd is in nonblocking mode */
- if (safe_read(signal_pipe.rd, &sig, 1) != 1)
+ if (safe_read(READ_FD, &sig, 1) != 1)
return 0;
return sig;